Pressure-gage.



PATENTBD MAR. 24, 1903-v G. J. MANNING.

PRESSURE GAGE.

APPLICATION FILED AUG. 12, 1002.

10 MODEL.

iUNtTEn STATES ATEN Enron;

COLEMAN J. MANNING, OF MEDFORD, MASSACHUSETTS.

' PRESS URE-GAG E.

SPECIFICATION forming part of Letters Patent No. 723,61 6; dated. March 24, 1903. Application filed AngnstIZ, 1902. Serial No. 119.451. (No model.)

To all whom, it may concern.-

Be it known that I, COLEMAN J. MANNING, a citizen of the United States, residing at Medford, in the county of Middlesex and State of Massachusetts, have invented a new and use ful Improvement in Pressure-Gages, of which the following is a specification.

My invention relates to pressure-gages for steam-hoilers and a'nalogons uses and is an improvement in particular upon such gages as employ the Bourdon tubular spring or springs, an example of which is describedin Letters Patent of the United States No. (377,674, issued to me July 2, 1901.

The object of my present invention is to facilitate the assembling of the parts of the gage in a complete working combination by making the index-movement adjustable in such manner as to secure greater accuracy and nicety in the practical operation of the gage and also to thereby efiect an important saving in time and cost of completing the same.

lattain the object stated by means of the construction and arrangement in respect thereto, which is hereinafter more particularly described, and illustrated in the accompanying drawings, in which Figure 1 is a plan showing a pressure-gage of the character referred to, showing an adjustable index-movement constructed in accordance with my present invention, the dialface being shown as broken away to disclose the interior parts. Fig. 2 is asimilar plan of the index-movement alone with its upper plate shown only in dotted outline. Fig. 3 is a perspective of a detached portion of the parts dex-movement, and the Bonrdon tubular spring E, with which the index-movement is connected and by which it is actuated. The

standards fixed in'plate F,- as shown.

index-movement by itself comprises a bedplateF, which, as represented in Fig. 4, has heretofore been firmly and immovably attached to a determined position in the case. When the-gage is in a. horizontal position with the face upward, as viewed in Fig. 1, plate Got the index-movement appears as an upper plate supported on and secured to A vertical spindle H, to which the index 0 is attached, is support-ed byplates Fand Gand arranged to turn therein in the usual manner. A spring I is coiled around said spindle and attached to the same' at one end, while the other end is secured to one of the upright standards. This spring offers a slight resistance to the rotation of the spindle in either direction, thereby tending to hold the index in its idle position, or at zero. A small pinion J is also attached to spindle H and is engaged by the teeth K on the sector-lever L, which lever is in two slotted and overlapping parts united by screws, so as to be longitudinally adjustable, and is arranged to rock on a pivoted standard M and by such rocking to impart a proper rotative movement to index 0. The outer end of sector-lever L is connected by link N to a projecting ear P on the free end of spring E. The opposite end of the spring is, as usual, connected with the inlet steam-pipe S, and the free end of the spring is actuated by the steam pressure therein and imparts movement to the index through the link N and the group of mechanism 'D connected therewith.

It is the usual practicein assembling the various parts of the gage in the case 'to arrange them therein with reference to a common center, which is the center of thedial B. The index-spindle H coincides therewith, and the arc of the circular spring E is as nearly concentric with the dial as it is practicable to makeit. Determinateholes are drilled in the case, whereby the index-movement is located and permanently secured by screws threaded therein through its bed-plate, with the spindle Hin the common center. Gages thus constructed, even with highest skill, have proved to be defective as true indicators of pressure and too difficult, laborious, and costly in adj ustment. It is very difficult, if not impracticable, to form the tubular springs E of a uniform and nicely exact length for a given size of gage or diameter of dial. Hence it is necessary when the gage is constructed in the usual manner, as illustrated in Fig. 4, to make a special link N for each gage, thus requiring the exercise of nice skill and the expenditure of much time in properly adjustingthe same, and thereby largely increasing the cost. Again, the vibration of the free or working end of the spring is caused by the tendency of the steam-pressure therein to straighten the same. The different degrees of movement of the spring, according to the different degrees of steam-pressure therein, varies the normal arc of the spring accordingly. This variation affects the concentric relation of the parts more or less by throwing the are out of its true circumferential relation to the common center and disturbs the accuracy of the indications on the dial. No means have hitherto been discovered or employed that would effectively overcome the difficulties in the actuating-spring referred totand save time and expense in completing and adjusting the gages. By long experience as a workman in the manufacture of many thousands of such gages and by many experiments to remedy the defects referred to I have invented and made the simpleimprovementhereinafter described, that accomplishes the desired purpose and which consists, essentially, in making the index-movement of itself independ: ently adjustable. By so doing I am enabled to make the connecting-link N, as shown in Figs. 1, 2, 3, of uniform lengths and exact duplicates of each other, formed with punch and die, rapidly and cheaply and to be interchangeable in the gages regardless of the variations in the lengths of the tubular springs before referred to. A pin T is driven into one end of the link and extends through the same far enough to reach through the ear P on the end of the spring, as clearly shown in Fig. 3. The opposite end of the link is secured to the sector-lever by a screw, as shown.

I make a slot V in the bed-plate F, through which screw Wis threaded into the case, with its head overlapping the slot. By slackening screws Wand U the bedplate F by means of the slot V and suitable playon screw U may be swung to a limited extent around screw U, and thus be made adjustable to any deviation in the length of tube E without change in the connecting-link N. Such movement of bed-plate F as it carries with it the pivoted bearing M, around which the sector-lever L rocks, affords a compound adjustment, together with said longitudinally-adjustable lever, whereby the variations before referred to in the arc of the spring maybe neutralized in their effect upon the dial indications, and further opportu-- nity to adjust, in respect to the movement of the index, is afiorded through such provision for suitable movement of the bed-plate F, inasmuch as the axis H is also affected by such movement. Whenever the desired adjustment is thus obtained, a tightening of screws factory largely increased. With the discovery of such simple and practical means and method of compound adjustment the parts of gages can be assembled and organized for practical operation-in less than one-fifth the time required to complete gages in the old way, (illustrated in Fig. 4,) a fact which proves the great usefulness and advantage of the invention.

I claim 1. A pressure-gage embodying the combination of an inclosing case; adial; a tubular spring; an index-movement attached to the case so as to be movable, and having the axis of its index thereby made adjustable eccentrically to the dial center; and a link connecting said spring and'movement; all substantially as specified.

2. Apressure-gage com prising an inclosing case, a dial, a tubular spring, an index-movement, and a link connecting said spring and movement, the latter having a slotted bedplate and being thereby made adjustable to springs of varying lengths,connected by links of uniform construction, substantially as and for the purposes specified.

3. Apressure-gage embodying the combination of an inclosing case; a dial; a tubular spring; an index-movement attached to the case so as to be movable, and having the axis of its index thereby made adjustable relatively to the dial center, the movement also including an adjustable sector-lever by which the index is turned, and the pivotal bearing of which lever is also adjustable, with the movement, relatively to the dial center, thereby effecting a compound adjustment of the index; and a link connecting the spring and sector-lever; allsubstantiallyas specified.

COLEMAN J. MANNING.

Witnesses:

EUGENE HUMPHREY, JOTT GRANT.

ICC 

